My hon. Friend makes a very important point. I know the role she has played, in particular in the all-party group on the armed forces, and of course in the NATO Parliamentary Assembly. She is absolutely right, and there are sometimes coup and contrecoup elements of damage to the brain. There is also some evidence to suggest that some people diagnosed with post-traumatic stress disorder have actually been suffering from a brain injury.
Interestingly, the Ministry of Defence has done some of the most innovative work in relation to brain injuries—physical brain injuries, as it were—and it has been able to transfer some of the skills and research involved in that work to the wider population, which is all to the good. However, I think that the way in which the mind sits inside the brain and the brain sits inside the skull is one of the areas of research that is still underdeveloped, and we still need to do a great deal about it.
Other causes include brain tumours and chronic traumatic encephalopathy, where somebody may have had a series of relatively minor concussions. There is a complete misunderstanding of what concussion actually involves, particularly in sport. This might be leading to some of the long-term sustained problems of, for example, people in my own constituency who played rugby for many years and had repeated concussions. They may suffer from dementia, depression and anxiety in later life, but have no understanding that that may relate to a brain injury, rather than to anything else.